Perhaps you should try some spelling variations:
"dynamischen systems" » "dynamischen systemen", "dynamischer systeme", "dynamische systeme"
"economic systems" » "economic sectors"
"dynamics system" » "dynamic system", "dynamical system", "dynamisches system"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dynamical systems") OR ((("dynamic systems") OR ("economic systems"))))) OR ((("dynamischen systems") OR ("dynamics system")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"dynamical systems\") or (((\"dynamic systems\") OR (\"economic systems\"))))) or (((\"dynamischen systems\") or (\"dynamics system\"))))".
• Removing quotes may allow a broader search: (((( dynamical systems ) or ((( dynamic systems ) OR ( economic systems ))))) or ((( dynamischen systems ) or ( dynamics system )))).
• Adding a wildcard symbol may retrieve word variants: (((("dynamical systems") or ((("dynamic systems") OR ("economic systems"))))) or ((("dynamischen systems") or ("dynamics system"))))*.